The present invention concerns a grain loss monitor system for a combine harvester and particularly an arrangement for mounting sensors of the system.
Although grain loss monitor systems for combines are now well-known they are, in terms of the history of the combine, a relatively recent innovation. They are still fitted mostly as special rather than regular equipment and their sensors typically find themselves in a somewhat hostile environment, offering no very convenient resting place. Once mounted, parts of the sensor, especially if mounted at the discharge end of a straw walker, may in operation be subjected to a violent bombardment by grain and other particles, especially in corn harvesting and when a straw chopper is fitted. Sensors for the cleaning shoe are preferably fitted towards the sides of the shoe so as to be in a good sampling location. Their presence there typically interferes with access to the cleaning shoe for adjustment of chaffer and sieve. Until now the existence of these problems has resulted in compromise and acceptance of inconvenience tending to limit the effectiveness or utilization of the grain loss monitor. In some cases, the vulnerability and unreliability of sensor mounting arrangements has been such that the manufacturers have recommended removal of the sensors when operating in certain crops and conditions.